1. Field of the Invention
The invention relates to an image recording apparatus provided with a selective powder applying device for selectively applying powder, such as powder of a developer or microcapsules, to a recording medium.
2. Description of the Related Art
Image recording apparatuses have been known for copying an original picture on a photosensitive, pressure-sensitive recording medium formed by coating the surface of a backing with microcapsules. Among those known image recording apparatuses, an image recording apparatus, such as disclosed in U.S. Pat. No. 4,985,727, forms a chemical latent image of an original picture on the surface of a photosensitive, pressure-sensitive recording medium coated with microcapsules, and applies a developer selectively to the chemical latent image. This image recording apparatus employs photoconductive means to apply a powdery developer selectively to the surface of a photosensitive, pressure-sensitive recording medium coated with microcapsules. The microcapsules comprise a photosetting resin, which sets when exposed to light, and a color precursor which reacts with a developer to develop a color. Such microcapsules are disclosed in U.S. Pat. No. 4,399,209 and hence the description thereof will be omitted.
In the operation of this image recording apparatus, light emitted by a light source is reflected by the surface of a document. The reflected light carries image information because the same is reflected by the surface of the document in which an original picture is formed. The reflected light is projected on the image forming surface of a photosensitive, pressure-sensitive recording medium coated with the microcapsules to form a chemical latent image of the original picture on the image forming surface by selectively setting the microcapsules according to the image information. Concurrently, an image scanner scans the document to obtain image information and a laser light source emits a laser beam according to the image information. A photoconductive drum is exposed to the laser beam to form an electrostatic latent image of the original picture on the photoconductive drum. Then, a powdery developer is applied electrostatically to the electrostatic latent image formed on the photoconductive drum. Subsequently, the developer applied to the photoconductive drum is transferred to the image forming surface of the photosensitive, pressure-sensitive recording medium coated with the microcapsules and carrying the chemical latent image. Then, the photosensitive, pressure-sensitive recording medium and an ordinary recording sheet are joined closely for pressure-development. In the pressure-development, the microcapsules, which have not been exposed to light and have not set, collapse to shed the color precursor contained therein, the shed color precursor and the developer interact to develop a color. Since the pattern of the collapsed microcapsules corresponds to the original picture, a color image of the original picture is formed on the recording sheet. As is obvious from the foregoing, this image recording apparatus needs an image reading device, such as the scanner, to apply the granular developer selectively to the photoconductive drum.